package com.store.store.controller;

import com.store.store.util.R;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import javax.swing.*;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/common")
public class CommonController {

    //从配置文件中获得基本的文件存储路径
    @Value("${wmc.fileuri}")
    private String basePath;

    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //注意变量名需要和前端的传的文件变量名的名字相同
        //file是一个临时文件，需要转存到指定位置，否则本次请求完成后，文件会被清理

        //获得原始文件名
        String originalFilename = file.getOriginalFilename();
        //获得文件后缀名
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用UUID重新生成文件名，防止文件名称重复造成文件覆盖
        String filename = UUID.randomUUID().toString()+suffix;

        //判断路径是否存在
        File dir = new File(basePath);
        if(!dir.exists()) dir.mkdirs();

        try {
            file.transferTo(new File(basePath+filename));
        } catch (IOException e) {
            e.printStackTrace();
        }

        return R.success(filename);
    }

    /**
     * 文件下载
     * @param name
     * @param servletResponse
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse servletResponse){

        try {
            //输入流，通过输入流读取文件内容
            FileInputStream inputStream = new FileInputStream(new File(basePath+name));
            //输出流，通过输出流写回浏览器
            ServletOutputStream outputStream = servletResponse.getOutputStream();

            servletResponse.setContentType("Image/jpeg");

            int len=0;
            byte[] bytes = new byte[1024];
            while((len= inputStream.read(bytes)) !=-1 ){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
            outputStream.close();
            inputStream.close();


        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }



    }

}
